Bought this Zen 90 in April, has less than 20 flights and the canopy split in the front right-side this weekend. It is now unusable.

I removed the canopy and noticed hairline cracks around every screw point.

Is anyone else experiencing this?

Thanks

Yep, 2 of these at our field and I built both of them. Both have bad canopy's. The second one I fiberglassed the screw holes to prevent cracking. All this did was allow the canopy to crack around the glass. I think the only thing that "might' fix the problem is to glass the new canopy around the edges and use canopy glue and trim tape around the edges and toss the screw mounting system.

You're lucky to have gotten only hairline cracks after 20 flights. These 2 are trashed....

I thought I had finally found the perfect ARF. This canopy problem, along withe the published CG problem (published is 4.2 inches aft LE, actual is 6.5 inches) has left me numb and $400.00 poorer.

Here is what the manufacturer has to say about the canopy, and my reply:
==========================

Dear Sir,

If you think the failure was due to manufacturer's defect, please send the
canopy back to us and we will inspect the canopy. Sometimes fastening the
canopy too tight may induce unnecessay stress and cause premature failure.

AirBorne Models
2127-H South Vasco Road
Livermore CA 94550

With best regards,

AirBorne Models

===========================

I used the grommets included with the model, and there is no special instruction in the manual which specifies a maximum torque or notice of over-torque on the mounting hardware.

I hate to spend $6.00 on shipping just so you guys can say it is my fault. I will post my problem on the newsgroups to see if others have had this problem with your canopy.

I told World Models about your problems with the canopy, and here is their response:

----------------------------------
Dear Sir,

I built one of the ZEN 90 prototypes using the same screw and grommet system and it has been flying for over 50 flights until it crashed due to pilot error. As I pointed out in my last e-mail to you, pre-matured failure may be due to overstress of the mounting screws. 2 canopies installed by the same person may have the same overstress problem. We use the same screw grommet system in all our models, and only once in a while we have pre-matured failures due to thinning of edges.

With best regards,

AirBorne Models
-------------------------------------

Don't you just love this guy?

World Models needs a new US rep.

Well, Ive been around for 18 years in the hobby and know how things work. The reason I built the second one is because he liked my setup and wanted things done right, meaning throwing out most of the ARF stuff. Seems to me for the $0.50 it cost them for a new canopy, they would be replace it no questions asked for a $400 sale. Makes you wonder...

Replacing with an original canopy will no doubt restore original looks; I would hate to see mine break.

I finally stuck the entire canopy with canopy glue (no cracks yet) and have left the screws in loosely (not before strengthening the holes with slow cyno) and redrilling them. Then what happened? a week later the pilot fell inside the canopy..ha ha.. yeah the canopy was glued tight; however after juggling about a bit I managed to seat the pilot in his place, drilled a tiny hole from inside the fuselage and poured cyno into it. phew! ok so far.

FWIW I found on the Zen's canopy,if you drill the existing holes a little larger to match the size of the inner part of the grommet and do not over tighten the retaining screws,you won't have a cracking problem.I also tacked down the front and rear of canopy with canopy glue.